# Calculating Motor Regen During Constant Torque

I’m using the ODrive in a situation where constant torque is applied to a cyclic load, meaning torque is constant regardless of motor rotation direction. In the forward situation, where the torque and rotation are positive, I was able to calculate the current draw/power demands of the motor, but I’m not sure of the best way of how to do this during braking.
I’m currently planning on using this motor and a capacitor bank + power supply as a power source.
My goal is to use regenerative forward braking when the motor has positive torque but negative rotation, but I have no idea of how to calculate how much power the regenerative braking will be able to achieve. This is important as it will help me size both the capacitor bank and the power supply. From my understanding, motor regen is proportional to speed, which means that the regen will be minimal in cases where the cyclic load is quasi-static and maximum at higher frequencies.
Does anybody have any insight on the best way to approach this?

It’s just the reverse of the forward torque case, no special math. Power = Torque * Speed. Multiply the instantaneous speed by the desired braking torque and you’re done.

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It is worth noting, that you need to be using the SI unit system for Power to come out in the familiar format of Watts.
Torque is in Nm and Velocity is in radians per second. Or for linear movement, metres per second and Newtons force.

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